1. Field of the Invention
The present invention relates to the field of telecommunications. More particularly, the present invention relates to a method and a system for setting a priority level of a call.
2. Description of the Related Art
FIG. 1 is a schematic block diagram of a conventional telecommunications system 10 that includes terminal equipment 11 and 16, a central offices 12 and 15, toll switches 13 and 14, and a call status platform 18. Terminal equipment 11, such as a standard wired-line telephone, wireless telephone, a computer terminal or a facsimile machine, is connected to a central office 12 of a Local Exchange Carrier (LEC) over link 17a in a well-known manner. Central office 12 is connected to long distance toll switch 13, such as a 4ESS.TM. type tandem switch, over trunk 17b in a well-known manner. Toll switch 13 is connected to toll switch 14, which can also be a 4ESS.TM. type tandem switch, over trunk 17c in a well-known manner. Toll switch 14 is connected to a central office 15 of another LEC over trunk 17d, which, in turn, is connected to terminal equipment 16, such as a standard wired-line telephone, a wireless telephone, a computer terminal or a facsimile machine. Call status platform 18 is connected to CO 12 and provides an audible indication of the status of a dialed call to a caller in a well-known manner, such as a ringing signal or a busy signal, depending upon the conditions encountered by the dialed call.
Even though only two toll switches are shown, the system of FIG. 1 can include more than two toll switches. A plurality of call status platforms 18 can be connected throughout telecommunications system 10, in which case, a call status platform local to where a busy connection is encountered signals a busy indication signal in a well-known manner to a call status platform that is local to the call originating equipment. Additionally, while system 10 is shown configured for completing interLATA telephone calls, system 10 can be configured for completing intraLATA telephone calls.
A call from terminal equipment 11 to terminal equipment 16 is connected in a well-known manner to central office (CO) 12. Central office 12 connects the call to toll switch 13. Under normal conditions, the call is routed to toll switch 14 over trunk 17c, then to CO 15 over trunk 17d, and finally to terminal equipment 16 over link 17e. In the situation when any of trunks 17b, 17c, 17d and 17e are filled to capacity with other call traffic, that is, busy, terminal equipment 11 will receive an indication that the call cannot be completed because the lines are busy. A caller in such a situation can either hang up and abandon efforts to complete the call, or continue to dial the desired number attempting to connect to terminal equipment 16.
While the concept of a call priority level has been used for traffic management and provisioning, what is needed, nevertheless, is a way for a caller to change a priority level of a call at the caller's option so that the call will be handled on a higher priority basis.